It is planned to continue the investigation of the electrochemical oxidation of purines, purines, purine nucleosides and nucleotides at the pyrolytic graphite electrode. Such investigations will involve the use of linear and cyclic sweep voltammetry, coulometry, mass electrolysis followed by product isolation and identification. Techniques such as thin layer spectroelectrochemistry, double potential step chronoamperometry and fast-sweep cyclic voltammetry will be employed to investigate the mechanistic aspects of the electrode reaction and to gain information regarding the formation of unstable intermediates. The second aspect of the study is an investigation of the adsorption of purines, nucleosides, nucleotides and oligo and polynucleotides at mercury electrodes. Adsorption isotherms will be obtained and interpreted based on data obtained by means of differential capacitance studies at a dropping mercury electrode, or by direct surface tension measurements using a capillary electrometer. These studies will be used to find the area occupied by adsorbed molecules and hence their surface orientation as well as to measure the Frumkin attraction coefficient and the free energy of adsorption.